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        在数组中查找对象,子数组检查属性

        Find object in array with subarray checking an property(在数组中查找对象,子数组检查属性)
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                  本文介绍了在数组中查找对象,子数组检查属性的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着跟版网的小编来一起学习吧!

                  问题描述

                  我有下面的数组,每个元素都有另一个名为 FunctionalityChildren 的数组,我需要找到包含属性 ActionFull 的唯一对象等于一个变量,例如'/budget/allocation' 或'/预算"

                  I have the array below and each element has another array called FunctionalityChildren, I need find the unique object that contains the property ActionFull equal a variable, for example '/budget/allocation' or '/budget'

                  let bigArray = [
                        {
                          "FunctionalityID": 114,
                          "Name": "General Register",
                          "Action": "/general-register",
                          "Icon": "settings_input_composite",
                          "System_ID": 21,
                          "FunctionalityFather_ID": null,
                          "Active": 1,
                          "Priority": 1,
                          "FunctionalityChildren": [
                            {
                              "FunctionalityID": 115,
                              "Name": "Supplier",
                              "Action": "/supplier",
                              "Icon": "perm_contact_calendar",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 114,
                              "Active": 1,
                              "Priority": 1,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1251,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 115,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/general-register/supplier"
                            },
                            {
                              "FunctionalityID": 116,
                              "Name": "RPA",
                              "Action": "/rpa",
                              "Icon": "view_day",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 114,
                              "Active": 1,
                              "Priority": 2,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1252,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 116,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/general-register/rpa"
                            },
                            {
                              "FunctionalityID": 117,
                              "Name": "Cost Center",
                              "Action": "/cost-center",
                              "Icon": "home",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 114,
                              "Active": 1,
                              "Priority": 3,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1253,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 117,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/general-register/cost-center"
                            },
                            {
                              "FunctionalityID": 118,
                              "Name": "Departament",
                              "Action": "/departament",
                              "Icon": "donut_small",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 114,
                              "Active": 1,
                              "Priority": 4,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1254,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 118,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/general-register/departament"
                            },
                            {
                              "FunctionalityID": 119,
                              "Name": "Product Line",
                              "Action": "/product-line",
                              "Icon": "view_headline",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 114,
                              "Active": 1,
                              "Priority": 5,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1255,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 119,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/general-register/product-line"
                            },
                            {
                              "FunctionalityID": 120,
                              "Name": "Product",
                              "Action": "/product",
                              "Icon": "shopping_cart",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 114,
                              "Active": 1,
                              "Priority": 6,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1256,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 120,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/general-register/product"
                            }
                          ],
                          "ProfileFunctionalities": [
                            {
                              "ProfileFunctionalityID": 1250,
                              "Profile_ID": 68,
                              "Functionality_ID": 114,
                              "CanInsert": false,
                              "CanUpdate": false,
                              "CanDelete": false
                            }
                          ],
                          "ActionFull": "/general-register",
                          "HasFunctionalities": true,
                          "model": false
                        },
                        {
                          "FunctionalityID": 99,
                          "Name": "Budget Account",
                          "Action": "/budget-account",
                          "Icon": "monetization_on",
                          "System_ID": 21,
                          "FunctionalityFather_ID": null,
                          "Active": 1,
                          "Priority": 2,
                          "FunctionalityChildren": [
                            {
                              "FunctionalityID": 100,
                              "Name": "Sector",
                              "Action": "/sector",
                              "Icon": "account_balance",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 99,
                              "Active": 1,
                              "Priority": 1,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1258,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 100,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/budget-account/sector"
                            },
                            {
                              "FunctionalityID": 101,
                              "Name": "Group",
                              "Action": "/group",
                              "Icon": "group_work",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 99,
                              "Active": 1,
                              "Priority": 2,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1259,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 101,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/budget-account/group"
                            },
                            {
                              "FunctionalityID": 102,
                              "Name": "Account",
                              "Action": "/account",
                              "Icon": "attach_money",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 99,
                              "Active": 1,
                              "Priority": 3,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1260,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 102,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/budget-account/account"
                            },
                            {
                              "FunctionalityID": 103,
                              "Name": "Budget",
                              "Action": "/budget",
                              "Icon": "credit_card",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 99,
                              "Active": 1,
                              "Priority": 4,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1261,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 103,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/budget-account/budget"
                            }
                          ],
                          "ProfileFunctionalities": [
                            {
                              "ProfileFunctionalityID": 1257,
                              "Profile_ID": 68,
                              "Functionality_ID": 99,
                              "CanInsert": false,
                              "CanUpdate": false,
                              "CanDelete": false
                            }
                          ],
                          "ActionFull": "/budget-account",
                          "HasFunctionalities": true,
                          "model": false
                        },
                        {
                          "FunctionalityID": 105,
                          "Name": "Budget",
                          "Action": "/budget",
                          "Icon": "credit_card",
                          "System_ID": 21,
                          "FunctionalityFather_ID": null,
                          "Active": 1,
                          "Priority": 3,
                          "FunctionalityChildren": [
                            {
                              "FunctionalityID": 106,
                              "Name": "Allocation",
                              "Action": "/allocation",
                              "Icon": "note_add",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 105,
                              "Active": 1,
                              "Priority": 1,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1272,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 106,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/budget/allocation"
                            },
                            {
                              "FunctionalityID": 107,
                              "Name": "Copy",
                              "Action": "/copy",
                              "Icon": "content_copy",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 105,
                              "Active": 1,
                              "Priority": 2,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1273,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 107,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/budget/copy"
                            },
                            {
                              "FunctionalityID": 108,
                              "Name": "In And Out",
                              "Action": "/in-and-out",
                              "Icon": "swap_vertical_circle",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 105,
                              "Active": 1,
                              "Priority": 3,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1274,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 108,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/budget/in-and-out"
                            },
                            {
                              "FunctionalityID": 109,
                              "Name": "Account Accounting",
                              "Action": "/account-accounting",
                              "Icon": "assignment",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 105,
                              "Active": 1,
                              "Priority": 4,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1275,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 109,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/budget/account-accounting"
                            },
                            {
                              "FunctionalityID": 110,
                              "Name": "Event",
                              "Action": "/eventos",
                              "Icon": "shopping_cart",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 105,
                              "Active": 1,
                              "Priority": 5,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1276,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 110,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/budget/eventos"
                            },
                            {
                              "FunctionalityID": 111,
                              "Name": "Copy Counter",
                              "Action": "/copy-counter",
                              "Icon": "swap_vertical_circle",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 105,
                              "Active": 1,
                              "Priority": 6,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1277,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 111,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/budget/copy-counter"
                            }
                          ],
                          "ProfileFunctionalities": [
                            {
                              "ProfileFunctionalityID": 1271,
                              "Profile_ID": 68,
                              "Functionality_ID": 105,
                              "CanInsert": false,
                              "CanUpdate": false,
                              "CanDelete": false
                            }
                          ],
                          "ActionFull": "/budget",
                          "HasFunctionalities": false,
                          "model": false
                        },
                        {
                          "FunctionalityID": 112,
                          "Name": "Config",
                          "Action": "/config",
                          "Icon": "build",
                          "System_ID": 21,
                          "FunctionalityFather_ID": null,
                          "Active": 1,
                          "Priority": 4,
                          "FunctionalityChildren": [
                            {
                              "FunctionalityID": 113,
                              "Name": "Control Year Month",
                              "Action": "/control-year-month",
                              "Icon": "date_range",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 112,
                              "Active": 1,
                              "Priority": 1,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1263,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 113,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/config/control-year-month"
                            }
                          ],
                          "ProfileFunctionalities": [
                            {
                              "ProfileFunctionalityID": 1262,
                              "Profile_ID": 68,
                              "Functionality_ID": 112,
                              "CanInsert": false,
                              "CanUpdate": false,
                              "CanDelete": false
                            }
                          ],
                          "ActionFull": "/config",
                          "HasFunctionalities": true,
                          "model": false
                        },
                        {
                          "FunctionalityID": 121,
                          "Name": "Report",
                          "Action": "/report",
                          "Icon": "picture_as_pdf",
                          "System_ID": 21,
                          "FunctionalityFather_ID": null,
                          "Active": 1,
                          "Priority": 5,
                          "FunctionalityChildren": [
                            {
                              "FunctionalityID": 122,
                              "Name": "Report 1",
                              "Action": "/report-um",
                              "Icon": "picture_as_pdf",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 121,
                              "Active": 1,
                              "Priority": 1,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1265,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 122,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/report/report-um"
                            },
                            {
                              "FunctionalityID": 123,
                              "Name": "Report 2",
                              "Action": "/report-dois",
                              "Icon": "picture_as_pdf",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 121,
                              "Active": 1,
                              "Priority": 2,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1266,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 123,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/report/report-dois"
                            },
                            {
                              "FunctionalityID": 124,
                              "Name": "Report 3",
                              "Action": "/report-tres",
                              "Icon": "picture_as_pdf",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 121,
                              "Active": 1,
                              "Priority": 3,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1267,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 124,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/report/report-tres"
                            }
                          ],
                          "ProfileFunctionalities": [
                            {
                              "ProfileFunctionalityID": 1264,
                              "Profile_ID": 68,
                              "Functionality_ID": 121,
                              "CanInsert": false,
                              "CanUpdate": false,
                              "CanDelete": false
                            }
                          ],
                          "ActionFull": "/report",
                          "HasFunctionalities": true,
                          "model": false
                        },
                        {
                          "FunctionalityID": 125,
                          "Name": "Profile",
                          "Action": "/profile",
                          "Icon": "person",
                          "System_ID": 21,
                          "FunctionalityFather_ID": null,
                          "Active": 1,
                          "Priority": 6,
                          "FunctionalityChildren": [
                            {
                              "FunctionalityID": 126,
                              "Name": "New",
                              "Action": "/new",
                              "Icon": "plus_one",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 125,
                              "Active": 1,
                              "Priority": 1,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1269,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 126,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/profile/new"
                            },
                            {
                              "FunctionalityID": 127,
                              "Name": "List",
                              "Action": "/list",
                              "Icon": "view_list",
                              "System_ID": 21,
                              "FunctionalityFather_ID": 125,
                              "Active": 1,
                              "Priority": 2,
                              "ProfileFunctionalities": [
                                {
                                  "ProfileFunctionalityID": 1270,
                                  "Profile_ID": 68,
                                  "Functionality_ID": 127,
                                  "CanInsert": true,
                                  "CanUpdate": true,
                                  "CanDelete": true
                                }
                              ],
                              "ActionFull": "/profile/list"
                            }
                          ],
                          "ProfileFunctionalities": [
                            {
                              "ProfileFunctionalityID": 1268,
                              "Profile_ID": 68,
                              "Functionality_ID": 125,
                              "CanInsert": false,
                              "CanUpdate": false,
                              "CanDelete": false
                            }
                          ],
                          "ActionFull": "/profile",
                          "HasFunctionalities": true,
                          "model": false
                        }
                      ]
                  

                  上面的代码对我有用,但我认为还有另一个代码更糖,我想学习它:

                  The code above works for me but I think exist another code more sugar and I want learn it:

                  let all = bigArray.reduce((prev, next) => {
                     return prev.concat(next.FunctionalityChildren)
                  }, [])
                  
                  bigArray.reduce((prev, next) => all.push(next), [])
                  
                  let desired1 = '/budget'
                  let desired2 = '/budget/allocation'
                  
                  let element1 = all.find(e=>e.ActionFull === desired1) // return the object that contains ActionFull = '/budget' (can be father)
                  let element2 = all.find(e=>e.ActionFull === desired2) // return the object that contains ActionFull = '/budget/allocation' (can be child)
                  
                  console.log(element1)
                  console.log(element2)
                  

                  注意,如上所示,可以是父亲也可以是孩子.

                  Pay attention, as I showed above, It can be a father or a child.

                  推荐答案

                  下面是我们期望我们的通用 deepFind 函数工作的方式

                  Here's how we expect our generic deepFind function to work

                  deepFind (x => x.ActionFull === '/budget', bigArray)
                  // { FunctionalityID: 105, Name: 'Budget', ActionFull: '/budget' ... }
                  
                  deepFind (x => x.ActionFull === '/budget/allocation', bigArray)
                  // { FunctionalityID: 106, Name: 'Allocation', ActionFull: '/budget/allocation' }
                  

                  我将为您提供命令式风格的解决方案,希望这能让您思考需要如何构建函数调用.请注意,该程序将通过一组可能的解决方案开始迭代,但它会停止迭代并在找到匹配项后立即返回结果.使用 Array#reduceArray#mapArray#filter 不足以完成这项任务,因为它们没有我们的短路行为正在寻找

                  I'm going to give you the imperative style solution in hopes that this gets you thinking about how you will need to structure your function calls. Notice that this program will begin iterating thru a possible set of solutions but it stops iterating and returns a result as soon as a match is found. Using Array#reduce or Array#map or Array#filter is inadequate for this task as they do not have the short-circuiting behavior we're looking for

                  在您的浏览器中运行以下程序,这次使用简化的数据集.应该很容易理解我们是如何得出结果的

                  Run the program below in your browser, this time with a simplified data set. It's should be easy to follow how we arrive at the result

                  const data =
                    [ { a: 1, b: 1 }
                    , { a: 2, b: 2, c: { d: [ { e: 2 } ] } }
                    , { a: 3, b: { c: { d: { e: { f: 3 } } } } }
                    ]
                  
                  const deepFind = (f, obj = {}) =>
                  { if (Object (obj) === obj)
                    { if (f (obj) === true)
                        return obj
                  
                      for (const [ k, v ] of Object.entries (obj))
                      { const res =
                          deepFind (f, v)
                        
                        if (res !== undefined)
                          return res
                      }
                    }
                  
                    return undefined
                  }
                  
                  console.log
                    ( deepFind (x => x.a === 1, data)             // { a: 1, b: 1 }
                    , deepFind (x => x.e === 2, data)             // { e: 2 }
                    , deepFind (x => Array.isArray(x.d), data)    // { d: [ { e: 2 } ] }
                    , deepFind (x => x.f === 3, data)             // { f: 3 }
                    , deepFind (x => x.e && x.e.f === 3, data)    // { e: { f: 3 } }
                    , deepFind (x => x.z === 9, data)             // undefined
                    )

                  deepFind 适用于所有对象,包括数组

                  deepFind works for all objects, arrays included

                  const alpha =
                    [ [ 'a', 'b', 'c' ], [ 'd', 'e', 'f' ], [ 'g', 'h', 'i' ] ]
                  
                  deepFind (x => x [1] === 'h', alpha)
                  // [ 'g', 'h', 'i', ]
                  
                  deepFind (([ _0, _1, _2 ]) => _2 === 'f', alpha)
                  // [ 'd', 'e', 'f' ]
                  

                  deepFind 表达为函数式程序只需要将迭代循环转换为具有状态参数的递归函数.因为您自己设计了递归函数,所以您可以对这个程序所需的短路行为进行编码.

                  Expressing deepFind as a functional program requires only the translation of an iterative loop to a recursive function with state parameters. Because you design the recursive function yourself, you can encode the short-circuit behavior this program requires.

                  下面,deepFind 是使用纯函数表达式编写的.添加状态参数 vrest 但只有 fo 是由用户指定的,例如我们在上面做了.如果您不希望这些作为函数的公共接口的一部分,则可以使用内部辅助函数.

                  Below, deepFind is written using a pure functional expression. State parameters v and rest are added but only f and o are meant to be specified by the user, like we did above. If you didn't want these as part your function's public interface, an internal auxiliary function could be used instead.

                  const identity = x =>
                    x
                  
                  const None =
                    Symbol ()
                  
                  const deepFind = (f = identity, o = {}, [ _, v ] = [ None, None ], ...rest) =>
                    Object (o) === o
                      ? f (o) === true
                        ? o
                        : v === None
                          ? deepFind (f, null, ...Object.entries (o))
                          : deepFind (f, v, ...rest, ...Object.entries (o)) 
                      : v === None
                        ? undefined
                        : deepFind (f, v, ...rest )
                  

                  重新运行程序验证输出确实是一样的

                  Re-run the program to verify that the output is indeed the same

                  const identity = x =>
                    x
                  
                  const None =
                    Symbol ()
                  
                  const deepFind = (f = identity, o = {}, [ _, v ] = [ None, None ], ...rest) =>
                    Object (o) === o
                      ? f (o) === true
                        ? o
                        : v === None
                          ? deepFind (f, null, ...Object.entries (o))
                          : deepFind (f, v, ...rest, ...Object.entries (o)) 
                      : v === None
                        ? undefined
                        : deepFind (f, v, ...rest )
                  
                  const data =
                    [ { a: 1, b: 1 }
                    , { a: 2, b: 2, c: { d: [ { e: 2 } ] } }
                    , { a: 3, b: { c: { d: { e: { f: 3 } } } } }
                    ]
                  
                  console.log
                    ( deepFind (x => x.a === 1, data)             // { a: 1, b: 1 }
                    , deepFind (x => x.e === 2, data)             // { e: 2 }
                    , deepFind (x => Array.isArray(x.d), data)    // { d: [ { e: 2 } ] }
                    , deepFind (x => x.f === 3, data)             // { f: 3 }
                    , deepFind (x => x.e && x.e.f === 3, data)    // { e: { f: 3 } }
                    , deepFind (x => x.z === 9, data)             // undefined
                    )
                  
                  const alpha =
                    [ [ 'a', 'b', 'c' ], [ 'd', 'e', 'f' ], [ 'g', 'h', 'i' ] ]
                  
                  console.log
                    ( deepFind (x => x [1] === 'h', alpha)              // [ 'g', 'h', 'i', ]
                    , deepFind (([ _0, _1, _2 ]) => _2 === 'f', alpha)  // [ 'd', 'e', 'f' ]
                    )

                  最后,这是一个 deepFindAll.在这个程序的变体中,我们得到一个由零个或多个结果组成的 array,而不是得到一个单一的答案或 undefined.这演示了我在上一个示例中提到的辅助循环,也是生成器的一个漂亮用例.

                  Lastly, here's a deepFindAll. In this variation of the program, instead of getting a single answer or undefined, we get an array of zero or more results. This demonstrates the auxiliary loop I mentioned in the previous example and also a beautiful use case for generators.

                  作为练习,我鼓励您使用函数表达式代替辅助生成器重写下面的 deepFindAll

                  As an exercise, I encourage you to rewrite deepFindAll below using a functional expression in place of the auxiliary generator

                  const deepFindAll = (f, o = {}) =>
                  { const aux =
                      function* (f, o)
                      { if (Object (o) === o)
                        { if (f (o) === true)
                            yield o
                          for (const [ _, v ] of Object.entries (o))
                            yield* aux (f, v)
                        }
                      }
                    return Array.from (aux (f, o))
                  }
                  
                  const data =
                    [ { a: 1, b: 1 }
                    , { a: 2, b: 2, c: { d: [ { e: 2 } ] } }
                    , { a: 3, b: { c: { d: { e: { f: 3 } } } } }
                    ]
                  
                  console.log
                    ( deepFindAll (x => x.a === 1 || x.e === 2, data)  // [ { a: 1, b: 1 }, { e: 2 } ]
                    , deepFindAll (x => x.e !== undefined, data)       //[ { e: 2 }, { e: { f: 3 } } ]
                    , deepFindAll (x => x.z === 9, data)               // []
                    )

                  这篇关于在数组中查找对象,子数组检查属性的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持跟版网!

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